Cloning did not cause Dolly the sheep to get arthritis, scientists confirm

A new study has dismissed concerns that cloning caused early-onset osteoarthritis (OA) in Dolly the sheep.

Scientists from the University of Nottingham and the University of Glasgow have published a radiographic assessment of the skeletons of Dolly, Bonnie (Dolly’s naturally conceived daughter) and Megan and Morag (the first two animals to be cloned from differentiated cells) that shows no abnormal OA.

The study follows the team’s research last year into the Nottingham ‘Dollies’, a quartet of sheep cloned in 2007 from the same line as Dolly, that showed the cloned sheep to age the same as naturally born sheep.

According to their assessment of the skeletons, the OA observed within the skeletons is similar to that naturally conceived sheep and Nottingham’s healthy aged clones.

Professor Sandra Corr, Professor of Small Animal Orthopaedic Surgery who has since moved to Glasgow University, said: “We found that the prevalence and distribution of radiographic-OA was similar to that observed in naturally conceived sheep, and our healthy aged cloned sheep.

As a result we conclude that the original concerns that cloning had caused early-onset OA in Dolly were unfounded.”

The new study arose after the findings regarding the Nottingham ‘Dollies’.

Derived from the same cell line that produced Dolly, the four sheep originated from Professor Keith Campbell’s attempts to improve the efficiency of the cloning method somatic-cell nuclear transfer (SCNT) and were left as his legacy to the University of Nottingham.

Studying the ‘Dollies’, Kevin Sinclair, Professor of Developmental Biology, in the School of Biosciences, along with Corr and David Gardner, Professor of Physiology at Nottingham’s School of Veterinary Medicine and Science, found radiographic evidence of only mild or, in one case, moderate OA.

Images courtesy of the University of Nottingham.

Given that the ‘Dollies’ had aged so apparently normal, the team felt that their findings stood in too stark a contrast to reports that cloning had caused Dolly to suffer from early-onset OA. First emerging in 2003, reports stated that at the age of 5½ Dolly was suffering from OA.

However, the only formal record of any OA in Dolly was a brief mention in a conference abstract, stating that Dolly had OA of the left knee.

In the absence of the original records however, the team were compelled to travel to Edinburgh, where the skeletons are stored in the collections of National Museums Scotland.

With special permission from Dr Andrew Kitchener, Principal Curator of Vertebrates at National Museums Scotland, the team then performed the X-rays on Dolly and her contemporary clones to reassess that 2003 diagnosis.

Sinclair said: “Our findings of last year appeared to be at odds with original concerns surrounding the nature and extent of osteoarthritis in Dolly – who was perceived to have aged prematurely. Yet no formal, comprehensive assessment of osteoarthritis in Dolly was ever undertaken. We therefore felt it necessary to set the record straight.”

China’s energy needs are being blamed for global carbon emissions rising for the first time in four years

China’s growing energy needs have been blamed for global carbon emissions rising in 2017, following three years of them remaining constant.

Research conducted by the University of East Anglia (UEA) and the Global Carbon Project has suggested emissions in China are projected to grow by approximately 3.5% in 2017.

Even though there has been an increased effort to use green energy within the nation, coal use is up an estimated 3%, oil use is up 5% and natural gas use is up nearly 12% in China.

“The green economy is booming in China and elsewhere, but growing energy demands are also being met with new oil, coal and natural gas infrastructure,” said Stanford University scientist Rob Jackson, who chairs the Global Carbon Project.

Image courtesy of University of East Anglia

In their paper, published in in the journals Nature Climate ChangeEarth System Science Data Discussions and Environmental Research Letters, the researchers forecast that global fossil fuel emissions will reach a record 37 billion tons of carbon dioxide in 2017, with total emissions reaching a record 41 billion tons, including deforestation.

“Global CO2 emissions appear to be going up strongly once again after a three year stable period. This is very disappointing,” said lead researcher Prof Corinne Le Quéré, director of the Tyndall Centre for Climate Change Research at UEA

“With global CO2 emissions from human activities estimated at 41 billion tonnes for 2017, time is running out on our ability to keep warming well below 2ºC let alone 1.5ºC.

“This year we have seen how climate change can amplify the impacts of hurricanes with more intense rainfall, higher sea levels and warmer ocean conditions favouring more powerful storms. This is a window into the future. We need to reach a peak in global emissions in the next few years and drive emissions down rapidly afterwards to address climate change and limit its impacts.”

Image courtesy of University of East Anglia

While emissions are predicated to rise in China, the researchers expect CO2 emissions to decline by 0.4% in the US and 0.2% in the EU; although, these are smaller declines than during the previous decade.

Renewable energy has also increased rapidly, and 2017 should see another record set for the amount of renewable generating capacity being installed.

“This year’s result is discouraging, but I remain hopeful,” said Jackson. “In the US, cities, states and companies have seized leadership on energy efficiency and low-carbon renewables that the federal government has abdicated.”